iCloud Photo backup alternatives

I have a lot invested in the Apple/iCloud ecosystem. My Photos Library contains about 34K photos spanning 20 years. After reading Compromised Apple Gift Card Leads to Apple Account Lockout I want some insurance that I won’t lose access to all of my media if something should happen out of my control.

Does anyone have a reliable system for backing up their Photos Library that doesn’t involve cloud services? I used to keep a backup on an external hard drive, and I keep Time Machine backups of local data, but I’ve found over the years that old hard drives aren’t always reliable. I’ve also put some of my old physical photo backups on USB keys. Is that the best way?

And if I want to download the originals from my iCloud Library, how should I do it? Straight to external media? I think my MacBook Pro drive would fill up in a snap if I attempted it.

Any suggestions welcome! Especially if you have a system that works for you.

Are you looking for something specific to Photos? Personally, I feel that the combination of a nightly duplicate, Time Machine, and Backblaze backing up all my data is sufficient to protect my photos alongside everything else.

I got my iMac with enough storage to hold all my iCloud files without using optimize storage. Since I have everything local I can easily backup via CCC and BackBlaze.

If you are still looking for an alternative for iCloud Photos Backup, I saw this software in the Mac Geek Gab Podcast. Have not used it.

The clip I saw - https://www.youtube.com/watch?v=Y-UdI1SqgVo

what about the dropbox?